Air charge cooling device



June 1944- K. LCHNER EI'AL 2,350,784

AIR CHARGE COOLING DEVICE -Filed Sept. 26, 1939 2 sheetssheet 1 112013: A wer L'HA/EL P5725? AAPPuS June 6, 1944. w K. Lbl-INER EI'AL r 2,350,734

' AIR CHARGE COOLING DEVICE Fiied Sept. 26, 1939 2 Sheets-Sheet 2 Kwer Adm/EB Ps'rEe A Ap us Patented June 6, 1944 v OFFICE Kurt Liilmer and Peter Kappus, Munich,- Germany; vested in the Alien Property Application September 26, 1939, Serial No. 296.654

In Germany September 23, 1938 9 Claims.

This invention relates to a cooling device for the charging air for air-cooled radial engines especially double-row radial engines with the blower arranged in front of the cylinders.

7 It is well known that by precompressing the air in the blower the temperature of the charging air is raised to such a degree as to have a deleterious influence upon theworking conditions. In the constructions heretofore known the charging air was made to ilow through coolers interposed between the blower which is then arranged behind the cylinders and the corresponding cylinder. I

An object of the present invention as above mentioned is to arrange the cooling device with the blower arranged in front of the cylinders in a manner diilering considerably from the constructions already known.

According to the present invention there is provided around the periphery of the blower an annular cooler .which may be subdivided into single coolers, in which case the intermediate spaces between two neighboring coolers may be provided with bailles. The annular cooler or the single coolers may be formed with tubes arranged radially -orparallel or approximately parallel relatively to each other which tubes in Fig. 1 is a longitudinal sectional view, with "parts shown in elevation, of a radial engine adapted for aerocraft use and equippe with y improved cooling device;

Figs. 2 and'3 are vertical cross'sections taken. substantially on the lines A,A and 3-13 of Fig.

v 1, looking in the direction of the arrows.

' pressed .air as it passesfrom the blower 4 toward;

' cooler.

Fig. 4 is a vertical cross section similar to Fig. 3

showing an alternative arrangement of the cooling device: and

Fig. 5 is a horizontal detail section through the In the drawings the I ignates an aeroplane propeller and 2 aradial ensine mounted to rotate the propeller. A supercharge blower I is positioned in front of the engine I for rotation by the propeller shaft, and our improved cooler is arranged to cool the comthe engine 2. A ring shaped connecting conduit 1 I is provided with air-direct bailles l and directs the cooled air through pipes I leading to the 1 several engine cylinders. The cooling air is order to obtain'a great surface and a-more emclent transfer of heat are given a great length relatively to their width. To further increase the by means of spa'ced-plates'or ribs arranged normal to the tubes. To stilfen the tubesand to further increasethe heat transfer from the chargzing alr to the plates or ribs and. ilnallyto thecooling air the tubes according to the present inventionare subdivided'by walls into a plurality of conduita,

cooling effect the tubes are connected externally vA further advantage of the present construction consists in the fact that a certain number or all cylinders have a common cooler which causes the charging air for more cylinders to flow at first through the tubes of the coolers, which are ing to the several cylinders.

Further details and advantages will be understood from the following description.

The inventionis agrammatically illustrated v by way of example the accompanying-drawmgs, wherein: 1

- connecting conduit i.

guided to and through the cooler l by a suitable 1 formation of the cowling l, l; the cooler 4 ohmprises a series of radial conduits or canals i2 carrying the compressed air and ioined together by circumferential series of cooling ribs Ii (note Fig. 3) The inner extremitiesofthe radial conduits I! open into the peripheral outlet portion of the blower 3, and the outer'extrelnities of the radial conduits I: open into the ring shaped in Fig.4 is shown an alternative arrangement wherein the radial conduits I! are positioned parallel with each other in circumferentially spaced cooling sections, which are separated from each other by baflles it which are positioned to divert incoming air through the cooler sections.

In Fig. 5 is shown a modified construction whereby the conduiin I! may be strengthened by internal spaced air-guiding ribs It.

The course of the cooling air through the cooler I and to'the engine cylinders 2 is illustrated by horizontal arrowsinl'ig. 1 and the course of the air directed toIthe blower 3 is shown by the downwardly angling arrowin Fig. 1.

we claim: 1

l. Inan internal combustion engine having a plurality of radially positioned cylinders, in combination, a supercharger mounted co-alxially in 4 front of and drivably connected to said engine,

and means for guiding and cooling the air delivered by said supercharger to the cylinders ofs'aid engine, said means beingmounted over the I reference numeral I desing relationship to said cooling air passages,

whereby all of the air which would otherwise be blown upon the, engine must first pass through said means to cool the compressed air.

2. The combination according to claim 1, in which said air-guidingand cooling means comprises an annular radiator having a plurality ot radial passages leading from said supercharger to the cylinders of said engine, and a plurality of longitudinal passages extending through the radiator in heat-conducting relationship to said radi passages.

I 3. The combination according to claim 1, in

whiih said air-guiding and cooling means comp a plurality oi guiding and cooling units connected to and leading from the supercharger at one end, means interconnecting the other ends or said units with one another, means leading from said interconnecting means to each cylinder, each unit including a plurality of substantially parallel passages leading from said supercharger to said interconnecting means .and pinrality of longitudinal passages extending through said unit in heat-conducting relationship to said parallel passages. and baiiie means positioned between and taking up the entire space between individual units for directing all oi. the oncoming air therethrough.

4. In an internal combustion engine having one or more cylinders, in combination, a supercharger mounted in front oi. and drivably connected to said engine, and means for guiding and cooling inders of said engine, comprising a radiator mounted over the entire front of said cylinders,

2 I assonsa entire front of the radially positioned cylinders having a plurality of parallel passages leadin from said supercharger to said cylinders and a plurality of longitudinal passages extending through said radiator in heat-conducting rela- 6 tionship to said parallel passages.

. passages leading from the supercharger, sub- 10 dividing each passage intoa number of conduits.

6. The combination according to claim 4, in combination with a plurality of strengthening walls positioned in and extending through the passages leading from the supercharger, subdividing each passage into a numberp! conduits.

7. The combination according to claim 1, in which said air-guiding and cooling means comprises an annular radiator mounted about the periphery of said supercharger, having a plurality oi radial passages leading from said su'per- P charger to the cylinders of said engine, and a plurality. of longitudinal passages extending through the radiator in heat-conducting relationship to said radial passages. I

8. In an internal combustion engine having one or more cylinders, in combination, a supercharger mounted in .iront of and drivably connected to said engine, and means for guiding and cooling the air delivered by said supercharger to the cylinders of said engine,- including a radiator mounted over the entire. iront of said cylinders. whereby alloi. theair which would otherwise be 9 blown upon the engine must first pass through said radiator to cool the compressed air.

.8 9. The combination according to claim 1, in

combination with common means for intercon- 'necting the outer ends oi the passages leading from said supercharger, and conduits leadins from said common means to the individual cyl- 40 inders. the air delivered by said supercharger to the cyliroa'r manna.

PETER. KAPPUS. 

